The polarization of asteroids and comets, and especially the various models for polarization observations, are studied. The goal of this study is to compare existing models for polarization and their properties. Based on the results presented here a particular model and estimation technique can be found suitable for a certain types of polarization observations and research frames. With the polarization particularly the linear polarization ratio is referred here. The Sun radiates light or more generally electromagnetic radiation - in the framework of this study to an asteroid or to a comet - in where all the linear polarization planes are equally represented, i.e. non-polarized light. Depending on its surface structure the target might scatter the different polarization planes of the radiation with different intensities making the scattered radiation polarized. The ratio between the difference and the sum of the perpendicular and parallel polarized components is called the linear polarization ratio. The linear polarization ratio can tell the researcher something about the target properties, e.g. about the surface material composition, packing density and roughness. Some models have been developed for the linear polarization ratio, and the models can be fitted to the observations as a function of the phase angle. These models are fully empirical and are not based on actual physical modeling of the polarization event. The estimated models are, however, useful when comparing polarization properties between different targets with often quite sparse and limited observational data. The nonlinear regression analysis and also Bayesian nonlinear regression analysis are used in the model estimation. With the Bayesian method the a priori information about the behavior of the polarization curve can be utilized, making the estimation robust also in cases where the number of observations is small or the data is insufficient in other ways. The polarization is also studied as a function of the wavelength of light when the interest is in the effect of the wavelength on the polarization properties. Modeling these effects reliably requires a delicate selection of the proper model and the estimation technique. The possibilities of the multiple response and the hierarchical Bayesian regression analysis in modeling are studied. Suitable models for analyzing the polarization observations are presented and compared in the thesis, and some results concerning the wavelength effect in polarization are studied.

The aim of this licentiate thesis is to analyse how femininity is constructed in twelve portrait interviews of women in the dailies Dagens Nyheter (Stockholm) and Hufvudstadsbladet (Helsinki) in September 1996, and to explore the portrait interview as a media genre. The qualitative analysis has a feminist and constructionist perspective and is connected to critical text analysis. It was carried out on two levels: first, femininity is identified on the linguistic level by choice of words, and second on the level of content (topical motifs/themes). The portrait interview as a genre constitutes a third dimension in the analysis: The aim is not towards the identification of femininity, but rather towards the identification of the portrait interview a relatively unexplored media genre.
References (Swedish: omtal) to the principal character (or protagonist) are traced mainly through reference chains which consist of names, pronouns and substantive phrases. The interviewees were referred to by their full names in Dagens Nyheter (with the exception of the oldest and youngest interviewees, both of whom were mainly referred to by their first names), while the style of reference varied more in Hufvudstadsbladet. The position of the principal character was also analysed through her relation in the text to minor characters from her working life and from her private life. These minor characters maintained their subordinate positions in all of the portraits except that of the youngest principal character, in which the subsidiary voices became at least as strong as the voice of the principal character.
Three frequently-recurring topical motifs occurred in the portraits: The first involved explanations for the principal character s success divided into three categories, agent, affect and ambition, the second concerned using journeys or trips as symbols for turning points in life, and the third referred to the ambiguity in the contradiction between private (family/other private life) and public (work) life. This ambiguity is connected to the portrait interview as a text type (genre) which features conclusions at the end of portraits, which in turn is characteristic of reportage. However, the analysis showed that the conclusions of the portrait interviews often also included elements of ambiguity. This was evident in the contradictions be14 tween private and public life that arose in the portrait interviews that focused on these two spheres. The portraits that focused on the principal character s public life showed ambiguity on a more general level concerning questions about being a woman and having a profession, and they often ended with a description of some details of her private life.
The women in the portraits were all constructed as being successful, in terms of having achieved direct success, reflective success or success in the form of life wisdom. The women of direct success were described as ambitious individuals with no sidetracks on their life paths, while those of reflective success were described as active heroines who had received help from different agents, who could use their affects as enriching ingredients in life, but who in the end had control over their own lives (life stories). The elderly women were constructed as having achieved life wisdom and their portraits were focused upon the past.
The portrait interview as a genre is characterised by journalistic freedom (in relation to the more strict news genre), by a now room (Swedish nurum ) where the journalist meets the principal character (usually via spoken dialogue that she or he transforms into written text to be read by a mass-media audience) and by the relatively closed structure of the portrait. The portrait is relatively independent in relation to the news genre and in relation to the context of what has previously been written, what is being written at the time and what will be written in the future the principal character does not need to belong to the newspaper s usual gallery of actors. Furthermore, the principal character is constructed as being independent in relation to the subsidiary characters and other media actors. The conflict is within the principal character herself and within her life story, unlike the news genre in which equal actors are in conflict with each other. The portrait is also independent in relation to the news lifespan; the publishing timetable is not as strict as in the news genre, but is still dependent on the factors initiating the portrait.
The enclosures consist of a raw analysis of two of twelve portrait interviews and of copies of all portraits.

This licentiate's thesis analyzes the macroeconomic effects of fiscal policy in a small open economy under a flexible exchange rate regime, assuming that the government spends exclusively on domestically produced goods. The motivation for this research comes from the observation that the literature on the new open economy macroeconomics (NOEM) has focused almost exclusively on two-country global models and the analyses of the effects of fiscal policy on small economies are almost completely ignored. This thesis aims at filling in the gap in the NOEM literature and illustrates how the macroeconomic effects of fiscal policy in a small open economy depend on the specification of preferences.
The research method is to present two theoretical model that are extensions to the model contained in the Appendix to Obstfeld and Rogoff (1995). The first model analyzes the macroeconomic effects of fiscal policy, making use of a model that exploits the idea of modelling private and government consumption as substitutes in private utility. The model offers intuitive predictions on how the effects of fiscal policy depend on the marginal rate of substitution between private and government consumption. The findings illustrate that the higher the substitutability between private and government consumption, (i) the bigger is the crowding out effect on private consumption (ii) and the smaller is the positive effect on output. The welfare analysis shows that the less fiscal policy decreases welfare the higher is the marginal rate of substitution between private and government consumption.
The second model of this thesis studies how the macroeconomic effects of fiscal policy depend on the elasticity of substitution between traded and nontraded goods. This model reveals that this elasticity a key variable to explain the exchange rate, current account and output response to a permanent rise in government spending. Finally, the model demonstrates that temporary changes in government spending are an effective stabilization tool when used wisely and timely in response to undesired fluctuations in output. Undesired fluctuations in output can be perfectly offset by an opposite change in government spending without causing any side-effects.

The aged people in the target group of my study belong to generation, which has experienced the shift from agricultural society via industrial society up to the society which has been described as information society. They have grown up concurrently with the technological development, but during the recent years the technological development has accelerated. One can say that the older the target study group has come the more information technological skills they need to possess to be equal actors in our society. However, especially in case of aged people the learning and maintaining of skills in information technology has mainly been left dependent on their personal motivation.
The purpose of this report is to study the use of computers in the life of the aged people. The report studies the will and ability of the aged people to learn the skill of using computers, and the new possibilities which this brings into their lives. The study questions are the following: 1) Why the aged people start to use computers? 2) How the aged people benefit information technology in their own life? 3) How computers have extended the environment of the aged people? 4) What kind of problems the aged people have experienced in use of computers?
The research material consists of group interviews and individual interviews (total of 23 people). The interview material has been collected among the participants on information technology courses of the Senior University of Helsinki University during years 2004-2005. The research method used is theme interviewing. In addition, the material of opinions about information technology of people born in decades of 1920 and 1930, gathered as part of the Ikihyvä Päijät-Häme 2002 -research has been used.
On basis of this research one can say that the aged people do have motivation to study the use of computers, although many interviewees commented that they also have met problems in use of computers. The motivation has grown also because the fear that without the skills to use computers they could drift into outsiders of the society, whereas instead as skilled computer users they felt to be equal citizens compared with the younger age groups, and that they can maintain their independence and autonomy. Especially, the independent use of banking routines over the Internet and use of emails seem to give them a position as modern actors. Many interview statements also underline that computers will bring both joy and benefit to the users.
Studying the use of computers is a new and interesting hobby, which can fill the hole left in the life after leaving the working life. Using skills of text processing and processing of pictures one can, for example, record the traditional knowledge of the family and ancestry to the younger generations, and write articles or even books on the professional area of ones own.
Single people emphasize that computers can even act as companionship substitutes. One can use Internet for virtual traveling, which provides a new dimension in use of computers. Internet can also be used to maintain family relationships, especially between grandparents and remote grandchildren.
Typical problems in use of computers appeared to be that reaching the right professional helpdesk advisers of the service providers is difficult and requires lots of time and patience. However, the interviewees were not willing to give up their computers, because they had already used to these.
Keywords: digital divide, aging, Internet, usability, motivation, information technology, information society.

The main aim of this work is to study the possibility of applying the cooperative learning approach to develop academic learning and teaching culture. In this work cooperative learning refers to a pedagogical approach that applies social psychological knowledge of group dynamics and small group teaching. Furthermore, theories of collaborative learning and organization development have been applied. Based on these theories a model of developing learning and teaching culture was developed. The model was tested in the development project that was carried out in the Faculty of Agriculture and Forestry of Helsinki University.
The research questions were: How were the theories of cooperative and collaborative learning and organization development applied in the project? What kind of effects did the development project have on the learning and teaching culture? Through which kind of mechanisms did the project influence this culture? How should the development model be revised after the empirical test?
The project lasted five years and the major part of the project consisted of a one-year pedagogical training course. Altogether 145 people (teachers, researchers, library staff, and students) participated in the training, two to three departments at a time. In the pedagogical training cooperative learning methods were widely used.
A questionnaire was used to study effects of the development project. The questionnaire was sent to 87 people and 65.5 % answered it. Both the answers to the questionnaire and a sample of learning diaries (n=61) were used to study the mechanism of the project. A sample of the learning diaries consisted of two pedagogical training group members diaries. The frequency distributions were calculated as extrapolations from the answers to the structured questions. Furthermore the answers were classified by the main background variables. The analysis of the open answers to the questionnaire and the learning diaries were data-based.
According to the answers to the questionnaire, the effects of the pedagogical training were as follows: The participants consider learning more as an active process of constructing knowledge. Furthermore they considered the individual learning styles and strategies, cooperation and motivation as more important part of the learning process than before the pedagogical training. The role of the teacher was viewed more challenging than before. Additionally the cooperation between teachers, other staff members and students had projected to increase. After the project had ended the teaching methods in the whole faculty were viewed to become varied and the teaching was considered to be more valued than before.
According to the answers to the questionnaire, the project influenced through the following ways: the project stimulated the change process, provided new methods for learning and teaching, had an effect on conceptions of learning and teaching and facilitated meaningful communication with others (staff and students). The analysis of the learning diaries supported these findings. In addition, the analysis of the learning diaries deepened the understanding of how the cooperative learning methods supported positive learning atmosphere and reduced the negative effect of the status differences between the members of the group. The critical comments in the learning diaries could be interpreted as collision between cooperative and traditional teaching culture.
Cooperative learning gives theory-based methods to develop academic learning and teaching culture. The approach helps the developer to create positive collaborative learning environment and gives ways to support learning in small groups, which can promote cultural change. On the other hand, to understand the whole process of organization development and promote change the theories of organizations and more sosioconstructivist theory of learning are needed.
Cooperative learning, collaborative learning, higher education, group dynamics, social constructionism, organisational culture, organisation development